Misplaced Pages

Ammonium dihydrogen phosphate

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.

This is an old revision of this page, as edited by 124.176.44.32 (talk) at 06:18, 30 July 2011. The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Revision as of 06:18, 30 July 2011 by 124.176.44.32 (talk)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)
Ammonium dihydrogen phosphate
Ball-and-stick model of the dihydrogenphosphate anion
Ball-and-stick model of the dihydrogenphosphate anion
Ball-andstick model of the ammonium cation
Ball-andstick model of the ammonium cation
Names
IUPAC name ammonium dihydrogen phosphate
Other names monoammonium phosphate
Identifiers
CAS Number
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.028.877 Edit this at Wikidata
E number E342(i) (antioxidants, ...)
CompTox Dashboard (EPA)
InChI
  • InChI=1S/H3N.H3O4P/c;1-5(2,3)4/h1H3;(H3,1,2,3,4)Key: LFVGISIMTYGQHF-UHFFFAOYSA-N
  • InChI=1/H3N.H3O4P/c;1-5(2,3)4/h1H3;(H3,1,2,3,4)Key: LFVGISIMTYGQHF-UHFFFAOYAX
SMILES
  • P(=O)(O)O.
Properties
Chemical formula H6NO4P
Molar mass 115.025 g·mol
Appearance white tetragonal crystals
Density 1.80 g/cm
Melting point 190 °C (374 °F; 463 K)
Solubility in water 40.4 g/100 mL
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
1 0 0
Thermochemistry
Std enthalpy of
formation (ΔfH298) 		-1445.07 kJ/mol
Related compounds
Other anions Ammonium phosphate
Diammonium phosphate
Other cations Monosodium phosphate
Potassium dihydrogen phosphate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). checkY verify (what is  ?) Infobox references
Chemical compound

Ammonium dihydrogen phosphate (ADP), or monoammonium phosphate, NH4H2PO4, is formed when a solution of phosphoric acid is added to ammonia until the solution is distinctly acidic. It crystallizes in tetragonal prisms. Monoammonium phosphate is often used in the blending of dry agricultural fertilizers. It supplies soil with the elements nitrogen and phosphorus in a form which is usable by plants. The compound is also a component of the ABC powder in some dry chemical fire extinguishers. This substance is also supplied in an emerald green or aquamarine crystal growing box kit for children.

Solid monoammonium phosphate show a dissociation pressure of ammonia of 0.05 mmHg at 125°C based on the decomposition reaction as follows:

NH4H2PO4(s) ⇌ NH3(g) + H3PO4(l)

ADP is a widely used crystal in the field of optics due to its birefringence properties. As a result of its tetragonal crystal structure, this material has negative uniaxial optical symmetry with typical refractive indices no=1.522 an ne=1.478 at optical wavelengths.

ADP crystals are piezoelectric which is a property required in some active sonar transducers (the alternative being transducers that use magnetostriction). In the 1950s ADP crystals largely replaced the Quartz and Rochelle Salt crystals in transducers because they are easier to work than Quartz and, unlike Rochelle Salt, are not deliquescent.

References

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.
Find sources: "Ammonium dihydrogen phosphate" – news · newspapers · books · scholar · JSTOR (July 2009) (Learn how and when to remove this message)
  1. Lide, David R. (1998). Handbook of Chemistry and Physics (87 ed.). Boca Raton, FL: CRC Press. pp. 4–40. ISBN 0-8493-0594-2.
  2. John R Van Wazer (1958). Phosphorus And Its Compounds - Volume I: Chemistry. New York: Interscience Publishers, Inc. p. 503.
  3. Amnon Yariv,Pochi Yeh (1984). Optical Waves in Crystals. Wiley, Inc.
  4. Willem Hackmann (1984). Seek and Strike: Sonar, Anti-Submarine Warfare and the Royal Navy, 1914–1954. Her Majesty's Stationery Office. ISBN 0-11-290423-8.
Categories: